Wanderfound

Anyone got an updated version of these graphs for the nerfed engines in the new FAR?

Ain't nothing stopping you from hooking a part test or two to your SSTO, and that's what I usually do. The fuel bill of around √5,000 is usually massively outweighed by the profits.

You need to watch the direction of your fuel lines; fuel flows from where you place the start of the line to the end. If there are multiple tanks in series, the furthest will drain first. For a simple asparagus with a core and four boosters, run fuel lines from two opposite boosters to the other pair of boosters, then run fuel lines from that pair to the core. The first pair will drain, then the second, then the core. You always drop them in pairs to maintain balance.

Yeah. Wheaton's Law seems like it might be appropriate here: http://knowyourmeme.com/memes/wheatons-law

Yup, same trick here. Get to 30,000, shut off everything except the central turbo, hello Mach 5. The only reason the D7 has a pair of turbos on the centre line was that the tuning-fork layout of the design made a central engine impossible (but it has enough inertia that a brief asymmetric thrust near the centreline is no big deal). This is also why I usually switch modes manually on the RAPIERs; if you wait for the auto-shift, they may not go at quite the same time.

Another trick: don't shut down the air breathers as soon as you activate the rockets. Air pressure is a function of both altitude and speed; when you light the fireworks, the acceleration should increase the effective pressure on your intakes and kick the jets back into life. Do shut the intakes if the jets die, though; they create a huge amount of drag.

With spaceplanes, the general idea is to maximise both your horizontal speed and altitude before lighting the oxidising fireworks. Basically, get into the thin, low-drag air as fast as you can (20,000m; you may want to keep at lower altitudes until you're over Mach 1 to avoid transsonic nose-tuck problems, though) before flattening out to build as much horizontal speed as possible (aim for at least 1000 m/s; get it just right and you can do better than 2,000m/s) before the engines choke at around 30,000m. Once they do, pull the nose up to 45 degrees, light the fuse and go to space. There are assorted tricks to extend how long the air lasts. Keep your climb rate and angle of attack as low as possible (by 30,000m they should be both be below ten), shut down engines in pairs rather than all at once, throttle down a bit once they start to gasp, etc. The problem with doing this with non-spaceplane SSTOs is that they usually have lousy horizontal flight capabilities. Just like with planes, if your CoL isn't behind your CoM then the thing is going to try and flip backwards when you level off.

Not quite a formal challenge, but see http://forum.kerbalspaceprogram.com/threads/85597-Building-a-Space-Swing-on-the-Mun! Scott Manley mentioned in his latest video that he'd like to try one. You've got a good first attempt there, but it's lacking a bit in scale. AFAIK, no one has yet successfully hung one off the arches. And if you get that done, there's always the Mun-circumnavigating rocket-powered monorail to build....

Ah, I forgot about the nukes; I don't like them, so I never use them. For interplanetary stuff, I use LV909's for small craft and Poodles for large. Anything with a 390 vacuum ISP, basically. In space, ISP is all that really matters; an LV909 will push just as much mass just as far for the same amount of fuel as a Poodle. It'll just take a lot longer to do it. Ditto for single vs multiple engines: regardless of the size of your craft, one engine will always be a smidge more efficient than two of the same engine (and two will be better than three, and so on), purely because it isn't pushing the extra mass of the second engine. if you don't have my LV-N aversion (I'm not actually anti-nuke; I used to work at a reactor. I just think they're a bit unbalanced in-game; they make long trips too easy), then the nukes are certainly the way to go. Again, a single engine is most efficient, but would be painfully slow. The limitation isn't anything in-game; the limiting factor is how long you're willing to sit there watching a burn happen.

The D7 was flying fine under .24; I didn't run into trouble until the Ferram update. And minor changes in mass aren't really an issue when you're dealing with a plane that can fly with a 70 ton payload. The only part clipping in the D7 is what you can do without the debug menu. It's mainly just that there's a probe core hidden in the fuselage so it can be flown as a drone. Mount girder section on the back of the fuselage, mount a probe core on top of that, then rotate the girder section inside the fuselage; you can stash most things with this trick. It's also how I got the shielded docking port mounted on the underside of the runabout (a cubic octagonal would be tidier, but I hadn't unlocked them yet on the save I built that in). The only wing overlapping was what was necessary to achieve the shape I wanted; you need to get creative when you're cooking with a limited range of ingredients. IIRC, the tailplane was made from two deltas, two rectangular structurals and two triangular structurals, mounted on another pair of rectangular structurals. It was the only way I could make the large delta form I was after.

And, to the point: why are you taking 120 tons to Eeloo? Most of my spacecraft aren't that heavy in total, including launch vehicles. As for engines: how patient are you? A single Ion would get you there eventually, but you'd chew your arms off in boredom during the hours-long burn. More realistically, you're probably looking at a bunch of Poodles. The optimum number would be as few as you can tolerate.

https://www.dropbox.com/s/et4mcneguukur4o/Kerbodyne%20D7%20revision%20WIP.craft is the current D7 prototype, BTW. Very much a work in progress, though; at the moment, the control surfaces are tearing off any time the angle of attack gets over fifteen degrees...

The D7 is being redesigned; the nerfing of air-breathing engines in the latest FAR update revealed some aerodynamic issues that I'd previously been able to power through. See the mod support thread ("power or aero?") if you're interested in how it's going. My little sports runabout is still flying well, though; the only thing I needed to change on that was to set the canards as flaps to give a bit more supersonic pitch authority. See https://www.dropbox.com/s/o7z87n1i1zqlv3n/Kerbodyne%20Overshoot%20VTOL.craft if you feel like taking it for a spin. The dinky VTOL jets are for Mun landings; don't try using them on Kerbin. I usually go for all-or-nothing on the intakes, but gradually shut engines down as I ascend to concentrate the thin air. The intakes are more than enough to feed the six engines at low altitude, but once you get to 30,000m you've only got enough for one pair, even with all intakes open. Shutting some intakes at low altitude reduces the drag, but I didn't really care about low altitude drag. Pre-nerf, the D7 could climb near vertically, so low altitude flight usually only lasted a minute or two. The surplus drag is trivial when you have that much thrust. My general approach was to climb as fast as possible to 18,000m, then level off into a slow climb to 30,000m, shutting off the RAPIERs in pairs as I go. Once the turbojets die (or get so weak that I start losing speed, typically around 30,000m/Mach 4.5), I pull up the nose and turn the RAPIERs back on. The ram-air effect would revive the turbojets and allow me to keep half of the RAPIERs on air-breathing mode for a bit longer. I'd typically have the apoapsis over 70km before the turbojets died completely and it was time to shut down the intakes. Still, splitting the intakes would be useful for fine control of air braking during reentry. But with the D7, I was running into an action group shortage: 1 was intakes, 2 for turbojets, 3 and 4 were the RAPIERs, 5 and 6 switched the RAPIER modes, 7 was the emergency brakes, 0 is always science on my planes and 9 was generally used for the cargo decoupling/undocking. 8 was the only one spare, and I often wanted that to activate something in the payload.

With rockets, I aim to have exactly enough fuel. I hate discarding a stage with unburnt fuel in it. With spaceplanes: as much fuel as I can lift. Ain't no point in getting to orbit if you've got no fuel left to do anything with. A properly designed spaceplane should be able to hit a 70km circular orbit with its tanks still half-full.

Ooh hang on: I just noticed the time acceleration thing. When you do that, your air readout will double (or triple, or quadruple) but the actual air available doesn't change. It's just an artefact of the physics compression.

Yup. Ram-air effect. It's a standard spaceplane tactic; fly until your air-breathers choke, then kick the rockets in to revive them. Do it right and you'll have the apoapsis over 70km before they choke again.

The "build a swing on the Mun" challenge is still outstanding...

As mentioned by others: spaceplanes. With a bit of work, you can do a stock-parts spaceplane that will lift a Rockomax 64 into orbit. If you land on the runway, the only expense is fuel. This should be less than √10,000 if you're doing it right.

You'll find the translation controls very helpful on final approach to docking; they allow you to move the velocity markers while keeping your nose on target for the port.

Cool, thanks. I'll try replacing the front centre gear with another lateral pair up front.

RCS has two sets of controls: turning and translating. Turning uses the usual ASDQEWX controls; translation uses IJKMHN. Turning RCS alters pitch/yaw/roll; translation RCS pushes you back/forwards/sideways.

The yellow marker shows the direction that you're moving relative to the target (target prograde); the pink marker shows the direction that the target is actually in. Each of these markers also has an opposite mark showing the reverse direction. If you burn directly towards the target prograde marker, you will increase your velocity relative to the target. If you burn directly towards the target retrograde marker, you will reduce your velocity relative to the target. The simplest way to do it is to wait until just before your closest approach and burn directly at target retrograde (the one that looks like the normal yellow retrograde marker) until your relative velocity (shown at the top of the navball when in target mode) hits zero. Then point directly at the target (the pink marker) and gently burn towards him. If you get the yellow marker on top of the pink one, that means that you're moving directly towards your target. To move the yellow markers, "push" retrograde and "pull" prograde. In other words, when you burn almost-but-not-quite prograde, the yellow prograde marker will move towards you. When you burn almost-but-not-quite retrograde, the retrograde marker will move away from you. Once you get in close, keep your nose pointed at the target and use the RCS translation controls (JKLIHN) to fine tune your approach speed and direction. PS: don't worry too much about your orbit during all of this. Once you end up next to your target with a zero relative velocity, you're going to automatically be in perfectly matched orbits.

Again: front gear, not rear. At the time that they're failing, there are seven sets of gear in contact with the ground, and the weight of the plane is shifting away from the gear that fail, not towards them.

You're missing some creative options if you do it that way. Place your Sepratrons right and you can make the boosters do ballet as they fall... (think Sepratron mounting angles, opposed rockets and spins)

Hmmn. We have new-FAR issues. Might be worth keeping it to a half-full tank until the engineers get it sorted.